Forensic Psychiatry, Pharmacogenetics & Adverse Drug Reactions

﻿

Adverse drug reactions

What happens when you take drugs (both pharmaceutical and street)?Nearly all medicines (and many environmental toxins) are metabolised (broken down, reorganised, redistributed and excreted) in the liver, by the different enzymes of the cytochrome P450 (CYP450) system.

Why do people react badly to drugs?Not all people are born with a full complement of metabolising enzymes, and sometimes the ones they do have are duplicated (genetic polymorphism), leading to compromised, absent, or very rapid metabolism of drugs. In this situation, side effects occur, ranging from mild to life-threatening. Side effects also occur with changes of dose, up or down, or when starting or stopping medication, and sometimes months after stopping. Once they set in, they are difficult to reverse.

Adverse drug reactions usually occur when any or all of the following are present:

There is a genetic problem in the cytochrome P450 (CYP450) family of metabolizing genes.

There is polypharmacy (the use of multiple concurrent medications), which can overload the system, compromising a person's ability to metabolise drugs.

There is a concurrent use of herbs and drugs, which can interact.

The dose is too high.

The drugs have been taken for a long period of time by a slow metaboliser.

When starting or stopping medication.

Signs of an adverse drug reaction

Weird, unwelcome and involuntary thoughts of suicide, death and dying.

Weird, unwelcome and involuntary thoughts of hostility, violence and homicide, found in people who have no

history of violent or disordered behaviour.

Akathisia, which can be intermittent or constant, is characterised by an inability to sit still, and is often associated with an extreme sense of impending doom and terror.

Do not stop taking your medication suddenly. If you do, you are at risk of more dangerous conditions, including akathisia, suicide attempts and other violent behaviour.

Find an experienced doctor, who can supervise a safe withdrawal from the culprit drug/s. Withdrawal is best done very slowly, over a period of months to years, utilising compounded medication, so brain chemistry can normalise. It is not possible to predict how a person will react to drug withdrawal, so it is important to be in the care of someone who can carefully monitor, and adjust your treatment as the situation dictates.

Psychiatric medication is highly addictive and many people experience their symptoms worsening during withdrawal period. These patients are sometimes mistakenly diagnosed with depression or "treatment-refractory schizophrenia", and the dose of a drug they already cannot metabolise is increased, or other drugs are added, leading to catastrophic non-recovery.

During withdrawal, it can be very helpful to have the support of people who understand what you are going through. Surviving Antidepressants offers online peer support.

It can take up to two years to feel like your normal self after withdrawing from psychiatric medication, as brain functioning issignificantly (and unpredictably) altered while a person is taking it.